This core will provide the framework for sustained communication among research projects, cores,[unreadable] governmental agencies, and interested parties through monthly seminars, our website, and meetings. A[unreadable] central theme of the proposed RTC activities is more direct involvement with ongoing priorities of selected[unreadable] governmental agencies responsible for minimizing human exposure to arsenic (As) and manganese (Mn)[unreadable] through domestic water supplies derived primarily from groundwater. Each public agency will be encouraged[unreadable] to identify and share relevant data holdings. We will integrate these multi-source data into an accessible[unreadable] Geographic Information System (GIS) and produce maps to enhance monitoring and regulatory decision[unreadable] making. The data integration will assist agencies and other stakeholders lacking GIS capacity and permit[unreadable] others to expand their capabilities. The public agencies involved are located in four states (NJ, NY, NH, ME)[unreadable] and include county as well as federal and state personnel. Our approach will be to integrate existing[unreadable] geophysical, geochemical, hydrological, and socio-demographic data for the Newark basin and adjacent[unreadable] areas of northern NJ and southern NY to assess sources (natural and anthropogenic) and human exposure[unreadable] to elevated groundwater As and Mn. These efforts will include field collaboration with government programs[unreadable] in Rockland County and six other counties in the Hudson valley. Environmental isotopes (tritium-3He) will be[unreadable] measured to derive groundwater recharge histories relevant to As and Mn concentrations. Landfills as a[unreadable] potential source for elevated groundwater As and Mn will be evaluated through joint field and laboratory[unreadable] measurements of iron (Fe) floe deposits, indicative of their mobilization in suboxic to anoxic groundwaters.[unreadable] Preliminary measurements of Fe floe chemistry adjacent to landfills indicate frequent high levels of As in[unreadable] areas that include large numbers of new homes using private wells. As part of an investigation of potential[unreadable] impacts of elevated drinking water As on cognitive function in children, two of our research projects will[unreadable] involve numerous measurements of groundwater chemistry in two New England states. We will integrate the[unreadable] new data into GIS formats compatible with those employed by public agencies in NH and ME to help[unreadable] evaluate patterns of exposure to As and Mn in groundwater. Information on exposure potential and treatment[unreadable] options will be shared with the public primarily through governmental agency communication channels.